The present invention relates to a method of cutting a gate on a vertical field effect transistor (VFET), and more specifically, to a method of cutting a gate on a VFET with a defined-width inorganic mask.
A metal-oxide-semiconductor field-effect transistor (MOSFET) is a transistor used for amplifying or switching electronic signals. The metal-oxide-semiconductor field-effect transistor has a source, a drain, and a metal oxide gate electrode. The metal gate is electrically insulated from the main semiconductor n-channel or p-channel by a thin layer of insulating material, for example, silicon dioxide or glass, which makes the input resistance of the metal-oxide-semiconductor field-effect transistor relatively high. The gate voltage controls whether the path from drain to source is an open circuit (“off”) or a resistive path (“on”).
N-type field effect transistors (NFET) and p-type field effect transistors (PFET) are two types of complementary metal-oxide-semiconductor field-effect transistor s. The N-type field effect transistor uses electrons as the majority current carriers and is built directly in a p substrate with n-doped source and drain junctions. The p-type field effect transistor uses holes as the majority current carriers and is built in an n-well with p-doped source and drain junctions.
The VFET is a type of metal-oxide-semiconductor field-effect transistor. The VFET contains a conformal gate around the fin that mitigates the effects of short channels and reduces drain-induced barrier lowering. “Vertical” or the “fin” refers to the narrow channel between source and drain regions. A thin insulating high-k gate oxide layer around the fin separates the fin channel from the gate metal.